James harris rogers



(No Model.)

J. H. ROGERS.

TELEPHONE TRANSMITTER AND RECEIVER.

Patented Jan. 2, 1883.

NrrE STATES PATENT JAMES HARRIS ROGERS, OF \VASHINGTON, D. 0., ASSIGNOR OF ONE-HALF TO FRANK HUME AND L. G. HINE, BOTH OF SAME PLACE.

TELEPHONE TRANSMITTER AND RECEIVER.

SPECIFICATION forming part of Letters Patent No. 269,884., dated January 2., 1883.

Application filed March 6, 1882.

(No model.)

T all whom it may concern.-

Be it known that I, JAMES HARRIS ROG- ERS, a citizen of the United States, residing at Washington, in the District of Columbia,

5 have invented new and useful Improvements in Transmitters and Receivers, of which thefollowing is a specification.

My invention relates to that class of telephones which are used either as transmitters or receivers, known as magneto-instruments, in which the telephonic effect is produced by magnetism.

The object of the invention is to produce an instrument without the ordinary membrane or 1 5 diaphragm, and which will yet readily respond to and reproduce and transmit all the tones of the human voice.

, To this end the invention consists in employing an electro-magnet one pole of which is placed in contact with the side casing or boxing ot' the instrument, which latter may be of any suitable material-such as wood, rubher, glass, &c. The vibrations or changes of the magnetic pole. in contact with the casingot' theinstrument, due to the variations ofelectrical current, will be taken up by the side piece of the instrument and rendered audible, and, similarly, sounds uttered in proximity to the'side of the instrument will cause vibrations :1 therein, which will be taken up by the pole of the magnet and variations of current produced in the line, as is well understood.

The invention further consistsin an improved device by which the receiving-telephone at a station is placed in circuit by a switch operated by the hand of the operator as he grasps the instrument to place it to his ear.

The details and special organizations, which will now be described, are fully shown in the .to accompanying drawings, in which Figure l is a horizontal section through my improved instrument, shown as arranged to be used as a receiver, and shows diagrammatically the ordinary induction-coil circuits and 5 the connections of a transmitter ata telephonic station. Figs. 2, 3, 4., 5, 6, and '7 are views. showing modified forms of magnets for my improved instrument, the apparatus illustrated in Fig. 7 being adapted for use as a receiver only.

Referring to Fig. 1, A is the case of the instrument, which may be of any suitable and usual non-conducting material, and is shaped, as usual, with the lengthened portion A, which is to be grasped by the operator. The case 5 may be made in any suitable manner with an open side or face at a, into which the magnet is inserted and over which is placed the resonant piece B, which takes up the vibrationsot' the pole of the electro-magnet. Of course the general construction of the case may be varied infinitely. The magnet M, which in this instance is of the ordinary horseshoe kind, is securely mounted by screws 0, or in any suitable manner, in the casing. The upper end of the leg of the magnet that is bolted to the case is bent and elongated at right angles, and the horizontal or elongated portion m carries the ordinary coil or'helix H, which is connected tothe line-wire L and secondary of the induc- 7o tion-coil I, as usual. The opposite leg, M, of the magnet is arranged in close proximity to the pole m, and rests in contact With the resonant side piece, 13, of the instrument, The

operation will be readily understood, and it 7 will be obvious that the instrument may be used either as a transmitter or a receiver. The resonant piece B is preferably formed with a concave face, 13, and surrounding annular flange b to present the appearance of an ordinarymouth-piece. Itisalsopreferably made a little thinner at the pointof contact with the pole of the magnet, as seen in the drawings. Neither of these featuresis essential, however, as the side may be made perfectly plain 8 and either round or rectangular. The concave face, however, serves a useful purpose in indicating the point against which to speak and the point to place to the ear.

In Fig. 2 the magnet is shown as being two 0 spools or helices, H, which may be connected I to different main circuits, as will be understood. ln F1031), a magnet is shown having both of the legs bent atri-ght angles and elongated toward each other, and each having a 5 helix, H, both of which helices may be included in different main circuits. This magnet may be applied and operated precisely as described and shown in Fig. 1. Fig. 4 shows 'a ring-magnet, also provided with a helix on each pole. Fig. 5 shows a horseshoe-magnet with soit-iron pole-pieces and a helix, H, on one pole only; and Fig. 6 shows a compound horseshoe-magnet similarly equipped. Fig. 7 shows a modification of the arrangement shown in Fig. 1. In the former figure a straight bar magnet, M, is shown as havingits end directly in contact with the resonant piece B. The general organization is similar to that shown in Fig. 1; but it is adapted for use as a receiver only. Changes of current will produce molecular changes in the magnetic core M, which cause corresponding vibrations in the piece B, against which it rests.

It will be noted that in myimprovediustrnwent there is no aperture in the casing and no membrane ordiaphragm, in atelephonicseuse, employed.

In order to insure the transmitter being placed in circuit at a station whenever the receiver is lifted to the ear, and to break the circuit of the transmitter whenever the receiver is laid down, I employ the following device: A switch, S, pivoted at 8, within the casing of the instrument, is connected with and normally held out of contact with the contactpoints 1) 1) by an elastic arm, S, secured on the outside of theinstrument. (See Fi .1.) When the operator grasps the instrument to place it to his ear in response to some call, he coinpresses the elastic arm, causing the switch to complete the circuit between the contact-points pp, and thus close. the circuitw m of the transmitter T, which circuit is the primary of an induction-coil, as is usual. \Vhen the operator has finished and lays the telephone down the circuit of the transmitter is immediately broken by the recoil of the elastic arm. Thus thelocal-battery circuit at astation isnormally open. By this device I an] enabled to absolutely assure the making and breaking of the transmitter-circuit whenever the telephone is taken up and laid down-an advantage obvious to those familiar with the subject. This operation does not depend on the telephone being placed in position upon a switch-hook after use, or upon the independent operation of any switch mechanism, which, so far as I am aware, has heretofore been the case.

Suitable call mechanism will of course be placed at each station.

I am aware that in a. telephone a flexible diaphragm has been vibrated by the impingement thereon of one pole or a projection of one pole of a. bentinagnet, the other pole of which carries a helix and operates upon the said impinging pole; and I do not claim such a telephone or a magnet arranged in such relation to atlexible diaphragm.

Having thus described my I claim is 1. In a telephone, the combinatiomwith the casing having a magnet-chamber, one outer wall of which is formed by an imperlorate sounding-piece having a mouth and ear piece formed integral therewith, of the bent magnet having one leg secured rigidly within the chamber and the polar portion of the other leg resting against the inner surface of said invent-ion, what sounding-piece, the poles of the magnet being ,in close proximity to each other, and the pole of the rigidly-secured leg carrying a surround ing helix arranged for connection in a mainline circuit, substantially as described.

2. The combination,with atelephonecarrying two contact-terminals, of the transm tter-circuit, a switch pivoted directly within the telephone-handle beneath the magnet and adapted to be worked by the grasp of the operator to make connect ions between the terminals placed on opposite sides of the switch-pivot, an'da device for automatically breaking the connection between the terminals when the telephone is laid down, substantially as set forth.

3. The combination of the telephone, the pivoted switch within the telephone-hamlle beneath the magnet, the contact-points on opposite sides of the pivot, and the elastic arm secured on the telephone, with which arm the switch is connected and by which it is operated, substantially as set forth.

In testimony whereof I have hereunto set my hand in the presence of two subscribing witnesses.

J. HARRIS ROGERS.

\Vitnesses:

JAMES L. NORRIS, James A. RUTHERFORD. 

